Before you hike off and take everyones off-hand recommendations about substitute filters take a look at the factory service bulletin for 6000 and 7000 series tractors that I posted at http://www.mytractorforum.com/showthread.php?t=87114. I became aware of this bulletin while talking to a factory rep from CC.
I have a late 6284 and found that the adapter and upgraded filter model were already on my tractor from the factory. But there was some reason why the filter model and adapter were upgraded, so I think you should check it out.
From other posts involving Cubs with hydrostatic transmissions it appears that they are very touchy regarding both the filters and the type of fluid used, so I would be careful about substitutions. I'm not sure saving ten or twenty bucks once in a while is worth risking several thousand dollars worth of hydro repairs later.
BTW - the guys at Houtz & Sons in Elburn, IL (630-365-6551) have been very helpful to me regarding advice and selling / shipping me filters and other components for my Cub. If you have questions I'm sure they can help you.